Senior Staff Analog Mixed-Signal Design and Modelling Engineer

Job description

**About IonQ:** [IonQ, Inc](https://cts.businesswire.com/ct/CT?id=smartlink&url=https%3A%2F%2Fionq.com%2F&esheet=54451094&newsitemid=20260316477473&lan=en-US&anchor=IonQ%2C+Inc&index=7&md5=0818ffbedc6dbad8c4d1611ac94c2a0f). [NYSE: IONQ] is the world’s leading quantum platform and merchant supplier - delivering integrated quantum solutions across computing, networking, sensing, and security. IonQ’s newest generation of quantum computers, the IonQ Tempo, is the latest in a line of cutting-edge systems that have been helping customers and partners including [Amazon Web Services,](https://cts.businesswire.com/ct/CT?id=smartlink&url=https%3A%2F%2Fionq.com%2Fnews%2Fionq-speeds-quantum-accelerated-drug-development-application-with&esheet=54451094&newsitemid=20260316477473&lan=en-US&anchor=Amazon+Web+Services%2C&index=8&md5=a7f94ee9b71a392dca3cd6c413722e51) [and](https://cts.businesswire.com/ct/CT?id=smartlink&url=https%3A%2F%2Fionq.com%2Fnews%2Fionq-speeds-quantum-accelerated-drug-development-application-with&esheet=54451094&newsitemid=20260316477473&lan=en-US&anchor=and&index=9&md5=2bed627b388878763f41ffe0e4edb16c) [AstraZeneca](https://cts.businesswire.com/ct/CT?id=smartlink&url=https%3A%2F%2Fionq.com%2Fnews%2Fionq-speeds-quantum-accelerated-drug-development-application-with&esheet=54451094&newsitemid=20260316477473&lan=en-US&anchor=AstraZeneca&index=10&md5=757c1f2c2ec94cf3982700106122164f) achieve 20x performance results and accelerate innovation in drug discovery, materials science, financial modeling, logistics, cybersecurity, and defense. In 2025, the company achieved 99.99% two-qubit gate fidelity, [setting a world record in quantum computing performance](https://cts.businesswire.com/ct/CT?id=smartlink&url=https%3A%2F%2Fionq.com%2Fnews%2Fionq-achieves-landmark-result-setting-new-world-record-in-quantum-computing&esheet=54451094&newsitemid=20260316477473&lan=en-US&anchor=setting+a+world+record+in+quantum+computing+performance&index=11&md5=32e9cb88afbd439026a352666cc72c91). Headquartered in College Park, Maryland, IonQ has operations in California, Colorado, Massachusetts, Tennessee, Washington, Italy, South Korea, Sweden, Switzerland, Canada, and the United Kingdom. Our quantum computing services are available through all major cloud providers, while we also meet the needs of networking and sensing customers across land, sea, air, and space. IonQ is making quantum platforms more accessible and impactful than ever before. **Location:** This role is based at our Oxford, England (UK) office, with the option to work a few days a week remotely. **Travel:** Up to 5% **Job ID:** 1765 **Role:** We are looking for a **Staff Analog Mixed-Signal Design and Verification Engineer** to join our **Cryo-CMOS IC team** at IonQ Oxford. In this role, you will design analog and mixed-signal blocks from specification through circuit design, simulation, layout, tape-out and silicon validation. You will also own top-level chip integration and modelling as a first-class part of our Cryo-CMOS development flow. In this you will build and maintain the model of the chip that the whole team simulates against, a mixed-abstraction model combining transistor-level circuits with Verilog-A/Verilog-AMS and SystemVerilog real-number behavioural blocks. You will decide which blocks are represented at which level of abstraction, keep the models faithful to the schematics and measured silicon. The full-chip model will then be used to verify the ASICs that control the quantum processor from room temperature down to a few kelvin. You'll play an important part in shaping the design, modelling and verification methodology, standards and sign-off criteria that support our work in building the world's most advanced quantum systems. **Responsibilities:** In this position, you will build and maintain the model of the chip that the whole team simulates against, a mixed-abstraction model combining transistor-level circuits with Verilog-A/Verilog-AMS and SystemVerilog real-number behavioural blocks. These models will be derived form first-principles mathematics and correlated against schematic and measured silicon. You will decide which blocks are represented at which level of abstraction, keep the models faithful to the schematics and measured silicon. The full-chip model will then be used to verify the ASICs that control the quantum processor from room temperature down to a few kelvin. You'll have the opportunity to set the design and modelling standards the programme signs off against, making trusted models to inform tape-out decisions, and raise the design and modelling capability of the engineers around you, contributing directly to the success of IonQ's quantum computing roadmap. Key responsibilities include: - Own the full-chip modelling strategy: model architecture, abstraction levels, accuracy targets and sign-off criteria used across the IC development flow - Owning analog and mixed-signal blocks (references, DACs, switches, regulators, clock distribution) from specification through schematic design - Own top-level integration: define block interfaces and specifications, assemble the top level, and run the full-chip mixed-signal simulations that verify the ASIC Develop Verilog-A and Verilog-AMS models of analog blocks and assemble them into a simulatable full chip - Build real-number models so the full chip runs in digital verification and regression at practical speed - Derive models from mathematics: turn a transfer function, a Z-parameter network description or a MATLAB analysis into robust Verilog-A with well-behaved tolerances - Define and run model-versus-schematic correlation, keeping models in sync with design releases, and feed measured silicon behaviour, back into the models and the block designs - Stand up mixed-signal co-simulation and regression (Cadence AMS Designer, Xcelium with Spectre) Lead block-level design reviews and mentor engineers on circuit design and modelling craft **Requirements:** To be successful, you will need deep analog and mixed-signal design and modelling experience, typically 10+ years. You will have designed blocks proven in silicon and models and used in production tape-out flows. You will bring expert transistor-level design of precision analog blocks (references, DACs, regulators, switches, clock distribution) taken through PVT and Monte Carlo, layout and silicon validation, together with expert Verilog-A and Verilog-AMS and strong real-number modelling. You’d be a great fit with: - Multiple tape-outs with responsibility for block design and top-level integration, including silicon bring-up and bench characterisation - Strong mathematical foundations: linear systems, Laplace and z-domain analysis, network (Z-) parameters, noise and non-linearity - Fluency in a production Cadence flow: Virtuoso, Spectre, Xcelium and AMS Designer or similar co-simulation environments, including parasitic extraction and post-layout sign-off - SystemVerilog, plus MATLAB or Python/NumPy for analysis and model validation; scripting to automate model generation, checking and regression - Cryogenic, space or other extreme-environment silicon experience will be highly beneficial, especially designing beyond foundry model validity using measured device data We're looking for someone who can design a block to specification and model it at the right fidelity, derive a model from equations and implement it end to end. You should be able to judge what to model and at what abstraction, align designers, verification and systems engineers on what a model does and does not promise, and contribute effectively within a fast-moving, highly technical team. Compensation will vary based on individual factors such as education, qualifications, and experience of the final candidate(s), specific office location, and calibration against relevant market data and internal team equity. Posted base salary figures are subject to change as new market data becomes available. Our benefits include comprehensive medical, dental, and vision plans, matching 401(k), unlimited PTO and paid holidays, parental/adoption leave, legal insurance, and a home technology stipend. Details of participation in these benefit plans will be provided when a candidate receives an offer of employment. At IonQ, we believe in fair treatment, access, opportunity, and advancement for all while striving to identify and eliminate barriers. We empower employees to thrive by fostering a culture of autonomy, productivity, and respect. We are dedicated to creating an environment where individuals can feel welcomed, respected, supported, and valued. We are committed to equity and justice. We welcome different voices and viewpoints and do not discriminate on the basis of race, religion, ancestry, physical and/or mental disability, medical condition, genetic information, marital status, sex, gender, gender identity, gender expression, transgender status, age, sexual orientation, military or veteran status, or any other basis protected by law. We are proud to be an Equal Employment Opportunity employer. **US Technical Jobs.**The position you are applying for will require access to technology that is subject to U.S. export control and government contract restrictions. Employment with IonQ is contingent on either verifying “U.S. Person” (e.g., U.S. citizen, U.S. national, U.S. permanent resident, or lawfully admitted into the U.S. as a refugee or granted asylum) status for export controls and government contracts work, obtaining any necessary license, and/or confirming the availability of a license exception under U.S. export controls. Please note that in the absence of confirming you are a U.S. Person for export control and government contracts work purposes, IonQ may choose not to apply for a license or decline to use a license exception (if available) for you to access export-controlled technology that may require authorization, and similarly, you may not qualify for government contracts work that requires U.S. Persons, and IonQ may decline to proceed with your application on those bases alone. Accordingly, we will have some additional questions regarding your immigration status that will be used for export control and compliance purposes, and the answers will be reviewed by compliance personnel to ensure compliance with federal law. **US Non-Technical Jobs.**Due to applicable export control laws and regulations, candidates must be a U.S. citizen or national, U.S. permanent resident (i.e., current Green Card holder), or lawfully admitted into the U.S. as a refugee or granted asylum. Accordingly, we will have some additional questions regarding your immigration status that will be used for export control and compliance purposes, and the answers will be reviewed by compliance personnel to ensure compliance with federal law. If you are interested in being a part of our team and mission, we encourage you to apply!